can: kvaser_usb: Ignore spurious error events after a busoff
PATCH 1/1 can: kvaser_usb: Ignore spurious error events after a busoff
From: Ahmed S. Darwish <[email protected]>
Sending data in high speed then introducing a busoff results in spurious BUS_ERROR events from the USBCan-II firmware directly _after_ the triggered BUS_OFF event.
In the current CAN state handling code, this will lead to an invalid can state of ACTIVE, ERROR, or PASSIVE even though the CAN controller has been already shut down due to the busoff.
Guard the state handling code from such invalid events.
Signed-off-by Ahmed S. Darwish <[email protected]>
--- drivers/net/can/usb/kvaser_usb.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-)
The patch is generated above linux-can-next tag:
`linux-can-next-for-3.20-20150128'
Scenario #1) Before the patch, send data then introduce a bus-off:
(1422904150.823691) can0 20000080 [8] 00 00 00 00 00 00 30 00 ERRORFRAME
bus-error
error-counter-tx-rx{{48}{0}}
(1422904150.823703) can0 20000084 [8] 00 20 00 00 00 00 80 00 ERRORFRAME
controller-problem{tx-error-passive}
bus-error
error-counter-tx-rx{{128}{0}}
(1422904150.823703) can0 20000080 [8] 00 00 00 00 00 00 88 00 ERRORFRAME
bus-error
error-counter-tx-rx{{136}{0}}
(1422904150.824039) can0 20000080 [8] 00 00 00 00 00 00 90 00 ERRORFRAME
bus-error
error-counter-tx-rx{{144}{0}}
(1422904150.824039) can0 20000080 [8] 00 00 00 00 00 00 98 00 ERRORFRAME
bus-error
error-counter-tx-rx{{152}{0}}
(1422904150.824040) can0 20000080 [8] 00 00 00 00 00 00 A0 00 ERRORFRAME
bus-error
error-counter-tx-rx{{160}{0}}
(1422904150.825038) can0 20000080 [8] 00 00 00 00 00 00 A8 00 ERRORFRAME
bus-error
error-counter-tx-rx{{168}{0}}
(1422904150.827325) can0 20000084 [8] 00 40 00 00 00 00 30 00 ERRORFRAME
controller-problem{back-to-error-active}
bus-error
error-counter-tx-rx{{48}{0}}
(1422904150.827334) can0 20000084 [8] 00 20 00 00 00 00 88 00 ERRORFRAME
controller-problem{tx-error-passive}
bus-error
error-counter-tx-rx{{136}{0}}
(1422904150.827335) can0 20000080 [8] 00 00 00 00 00 00 88 00 ERRORFRAME
bus-error
error-counter-tx-rx{{136}{0}}
(1422904150.827536) can0 20000080 [8] 00 00 00 00 00 00 90 00 ERRORFRAME
bus-error
error-counter-tx-rx{{144}{0}}
(1422904150.827536) can0 20000080 [8] 00 00 00 00 00 00 98 00 ERRORFRAME
bus-error
error-counter-tx-rx{{152}{0}}
(1422904150.827536) can0 20000080 [8] 00 00 00 00 00 00 A0 00 ERRORFRAME
bus-error
error-counter-tx-rx{{160}{0}}
(1422904150.828714) can0 20000080 [8] 00 00 00 00 00 00 A8 00 ERRORFRAME
bus-error
error-counter-tx-rx{{168}{0}}
(1422904150.828716) can0 20000080 [8] 00 00 00 00 00 00 B0 00 ERRORFRAME
bus-error
error-counter-tx-rx{{176}{0}} [[ Same transitions as in above 'active -> passive -> back_to_active'
several times... ]]
(1422904150.907488) can0 20000084 [8] 00 40 00 00 00 00 30 00 ERRORFRAME
controller-problem{back-to-error-active}
bus-error
error-counter-tx-rx{{48}{0}}
(1422904150.907496) can0 20000084 [8] 00 20 00 00 00 00 78 00 ERRORFRAME
controller-problem{tx-error-passive}
bus-error
error-counter-tx-rx{{120}{0}}
(1422904150.907497) can0 20000080 [8] 00 00 00 00 00 00 88 00 ERRORFRAME
bus-error
error-counter-tx-rx{{136}{0}}
(1422904150.908722) can0 20000080 [8] 00 00 00 00 00 00 98 00 ERRORFRAME
bus-error
error-counter-tx-rx{{152}{0}}
(1422904150.908724) can0 20000080 [8] 00 00 00 00 00 00 A0 00 ERRORFRAME
bus-error
error-counter-tx-rx{{160}{0}}
(1422904151.933234) can0 200000C0 [8] 00 00 00 00 00 00 00 7F ERRORFRAME
bus-off
bus-error
error-counter-tx-rx{{0}{127}}[[ Spurious bus error events after bus off ]]
(1422904151.933248) can0 20000084 [8] 00 40 00 00 00 00 38 00 ERRORFRAME
controller-problem{back-to-error-active}
bus-error
error-counter-tx-rx{{56}{0}}
(1422904151.933659) can0 20000084 [8] 00 20 00 00 00 00 80 00 ERRORFRAME
controller-problem{tx-error-passive}
bus-error
error-counter-tx-rx{{128}{0}}
(1422904151.933659) can0 20000080 [8] 00 00 00 00 00 00 88 00 ERRORFRAME
bus-error
error-counter-tx-rx{{136}{0}}
(1422904151.933660) can0 20000080 [8] 00 00 00 00 00 00 90 00 ERRORFRAME
bus-error
error-counter-tx-rx{{144}{0}}
(1422904151.935096) can0 20000080 [8] 00 00 00 00 00 00 98 00 ERRORFRAME
bus-error
error-counter-tx-rx{{152}{0}}
(1422904151.935098) can0 20000080 [8] 00 00 00 00 00 00 A0 00 ERRORFRAME
bus-error
error-counter-tx-rx{{160}{0}}
(1422904151.935100) can0 20000080 [8] 00 00 00 00 00 00 A8 00 ERRORFRAME
bus-error
error-counter-tx-rx{{168}{0}}[[ then silence ... ]]
$ ip -details link show can0 ... can state ERROR_PASSIVE ...
*********************************************************************
Scenario #2) After the patch, send data then introduce a bus-off:
(1422906019.370441) can0 20000080 [8] 00 00 00 00 00 00 30 00 ERRORFRAME
bus-error
error-counter-tx-rx{{48}{0}}
(1422906019.370449) can0 20000084 [8] 00 20 00 00 00 00 80 00 ERRORFRAME
controller-problem{tx-error-passive}
bus-error
error-counter-tx-rx{{128}{0}}
(1422906019.370450) can0 20000080 [8] 00 00 00 00 00 00 88 00 ERRORFRAME
bus-error
error-counter-tx-rx{{136}{0}}
(1422906019.370834) can0 20000080 [8] 00 00 00 00 00 00 90 00 ERRORFRAME
bus-error
error-counter-tx-rx{{144}{0}}
(1422906019.370836) can0 20000080 [8] 00 00 00 00 00 00 98 00 ERRORFRAME
bus-error
error-counter-tx-rx{{152}{0}}
(1422906019.370836) can0 20000080 [8] 00 00 00 00 00 00 A0 00 ERRORFRAME
bus-error
error-counter-tx-rx{{160}{0}}
(1422906019.371860) can0 20000080 [8] 00 00 00 00 00 00 A8 00 ERRORFRAME
bus-error
error-counter-tx-rx{{168}{0}}
(1422906019.374248) can0 20000084 [8] 00 40 00 00 00 00 30 00 ERRORFRAME
controller-problem{back-to-error-active}
bus-error
error-counter-tx-rx{{48}{0}}
(1422906019.374256) can0 20000084 [8] 00 20 00 00 00 00 88 00 ERRORFRAME
controller-problem{tx-error-passive}
bus-error
error-counter-tx-rx{{136}{0}}
(1422906019.374257) can0 20000080 [8] 00 00 00 00 00 00 88 00 ERRORFRAME
bus-error
error-counter-tx-rx{{136}{0}}
(1422906019.374441) can0 20000080 [8] 00 00 00 00 00 00 98 00 ERRORFRAME
bus-error
error-counter-tx-rx{{152}{0}} [[ Same transitions as in above 'active -> passive -> back_to_active'
several times... ]]
(1422906019.454078) can0 20000084 [8] 00 40 00 00 00 00 30 00 ERRORFRAME
controller-problem{back-to-error-active}
bus-error
error-counter-tx-rx{{48}{0}}
(1422906019.454086) can0 20000084 [8] 00 20 00 00 00 00 78 00 ERRORFRAME
controller-problem{tx-error-passive}
bus-error
error-counter-tx-rx{{120}{0}}
(1422906019.454086) can0 20000080 [8] 00 00 00 00 00 00 88 00 ERRORFRAME
bus-error
error-counter-tx-rx{{136}{0}}
(1422906019.454426) can0 20000080 [8] 00 00 00 00 00 00 90 00 ERRORFRAME
bus-error
error-counter-tx-rx{{144}{0}}
(1422906019.454427) can0 20000080 [8] 00 00 00 00 00 00 98 00 ERRORFRAME
bus-error
error-counter-tx-rx{{152}{0}}
(1422906019.454427) can0 20000080 [8] 00 00 00 00 00 00 A0 00 ERRORFRAME
bus-error
error-counter-tx-rx{{160}{0}}
(1422906019.455310) can0 20000080 [8] 00 00 00 00 00 00 A8 00 ERRORFRAME
bus-error
error-counter-tx-rx{{168}{0}}
(1422906019.455311) can0 20000080 [8] 00 00 00 00 00 00 B0 00 ERRORFRAME
bus-error
error-counter-tx-rx{{176}{0}}
(1422906019.455312) can0 20000080 [8] 00 00 00 00 00 00 B8 00 ERRORFRAME
bus-error
error-counter-tx-rx{{184}{0}}
(1422906020.470092) can0 200000C0 [8] 00 00 00 00 00 00 00 0A ERRORFRAME
bus-off
bus-error
error-counter-tx-rx{{0}{10}}[[ then silence ... ]]
$ ip -details link show can0 ... can state BUS_OFF ...
*********************************************************************
Scenario #3) regular cangen, then unplug, then re-plug:
[[ No change in behavior before or after the patch, as expected ]]
(1422897112.214942) can0 51D [4] FF 02 00 00
(1422897112.225063) can0 701 [8] 00 03 00 00 00 00 00 00
(1422897112.235218) can0 010 [5] 01 03 00 00 00
(1422897112.245331) can0 53B [8] 02 03 00 00 00 00 00 00
(1422897112.255331) can0 2DA [5] 03 03 00 00 00
(1422897112.265469) can0 20000080 [8] 00 00 00 00 00 00 00 01 ERRORFRAME
bus-error
error-counter-tx-rx{{0}{1}}
(1422897112.265571) can0 20000080 [8] 00 00 00 00 00 00 00 0A ERRORFRAME
bus-error
error-counter-tx-rx{{0}{10}}
(1422897112.266216) can0 20000080 [8] 00 00 00 00 00 00 00 13 ERRORFRAME
bus-error
error-counter-tx-rx{{0}{19}}
(1422897112.266219) can0 20000080 [8] 00 00 00 00 00 00 00 1C ERRORFRAME
bus-error
error-counter-tx-rx{{0}{28}}
(1422897112.266584) can0 20000080 [8] 00 00 00 00 00 00 00 40 ERRORFRAME
bus-error
error-counter-tx-rx{{0}{64}}
(1422897112.266586) can0 20000080 [8] 00 00 00 00 00 00 00 49 ERRORFRAME
bus-error
error-counter-tx-rx{{0}{73}}
(1422897112.266587) can0 20000080 [8] 00 00 00 00 00 00 00 52 ERRORFRAME
bus-error
error-counter-tx-rx{{0}{82}}
(1422897112.266693) can0 20000080 [8] 00 00 00 00 00 00 00 5B ERRORFRAME
bus-error
error-counter-tx-rx{{0}{91}}
(1422897112.267609) can0 20000084 [8] 00 04 00 00 00 00 00 64 ERRORFRAME
controller-problem{rx-error-warning}
bus-error
error-counter-tx-rx{{0}{100}}
(1422897112.267610) can0 20000080 [8] 00 00 00 00 00 00 00 75 ERRORFRAME
bus-error
error-counter-tx-rx{{0}{117}}
(1422897112.267821) can0 20000084 [8] 00 10 00 00 00 00 00 87 ERRORFRAME
controller-problem{rx-error-passive}
bus-error
error-counter-tx-rx{{0}{135}}
(1422897112.267822) can0 20000080 [8] 00 00 00 00 00 00 00 87 ERRORFRAME
bus-error
error-counter-tx-rx{{0}{135}}[[ Then same of the above ]]
(1422897119.890745) can0 190 [8] 04 03 00 00 00 00 00 00 (1422897119.890890) can0 749 [8] 05 03 00 00 00 00 00 00 (1422897119.891297) can0 3B5 [8] 06 03 00 00 00 00 00 00 (1422897119.891417) can0 74B [8] 07 03 00 00 00 00 00 00 (1422897119.891880) can0 5F6 [8] 08 03 00 00 00 00 00 00
drivers/net/can/usb/kvaser_usb.c +10 -9
@@ -11,7 +11,7 @@* Copyright (C) 2002-2006 KVASER AB, Sweden. All rights reserved. * Copyright (C) 2010 Matthias Fuchs <[email protected]>, esd gmbh * Copyright (C) 2012 Olivier Sobrie <[email protected]> -* Copyright (C) 2015 Valeo A.S. +* Copyright (C) 2015 Valeo S.A. */ #include <linux/completion.h>
@@ -824,14 +824,15 @@ static void kvaser_usb_rx_error_update_can_state(struct kvaser_usb_net_priv *prielse if (es->status &M16C_STATE_BUS_PASSIVE ) new_state =CAN_STATE_ERROR_PASSIVE ;else if (es->status &M16C_STATE_BUS_ERROR ) { -if ((es->txerr >=256 ) || (es->rxerr >=256 )) - new_state =CAN_STATE_BUS_OFF ; -else if ((es->txerr >=128 ) || (es->rxerr >=128 )) - new_state =CAN_STATE_ERROR_PASSIVE ; -else if ((es->txerr >=96 ) || (es->rxerr >=96 )) - new_state =CAN_STATE_ERROR_WARNING ; -else if (cur_state >CAN_STATE_ERROR_ACTIVE ) - new_state =CAN_STATE_ERROR_ACTIVE ; +/* Guard against spurious error events after a busoff */ +if (cur_state <CAN_STATE_BUS_OFF ) { +if ((es->txerr >=128 ) || (es->rxerr >=128 )) + new_state =CAN_STATE_ERROR_PASSIVE ; +else if ((es->txerr >=96 ) || (es->rxerr >=96 )) + new_state =CAN_STATE_ERROR_WARNING ; +else if (cur_state >CAN_STATE_ERROR_ACTIVE ) + new_state =CAN_STATE_ERROR_ACTIVE ; + } }if (!es->status)
Signature · 1 line
1.9.1
Quoted 6 lines · Ahmed S. Darwish
From: Ahmed S. Darwish <[email protected]>
Sending data in high speed then introducing a busoff results in spurious
BUS_ERRORevents from the USBCan-II firmware directly _after_ the triggeredBUS_OFFevent.
Quoted 7 lines
In the current CAN state handling code, this will lead to an invalid can state of ACTIVE, ERROR, or PASSIVE even though the CAN controller has been already shut down due to the busoff.
Guard the state handling code from such invalid events.
Signed-off-by Ahmed S. Darwish <[email protected]>
Applied to can-next.
Thanks,
Marc
Signature · 4 lines
Pengutronix e.K. | Marc Kleine-Budde | Industrial Linux Solutions | Phone: +49-231-2826-924 | Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |